Diaphragm for steam turbines



C. R. WALLER. v DIAPHRAGM FOR STEAM TURBINES. APFLICA'HON FILED JAN. 3, 1921. RENEWED JULY 3.1922.

Patented Aug. 29, 19-22.

GARL 1t. WALLER, OF TBJENTON, 111131717 JERSEY, ASSIGNOB- T0 DE TIA VAL STEAM TURBINE GQIeElE'l-XNY, 013 TRENTON NEW JERSEY, A COPEOBATION OF NEW JERSEY.

Specification of Letters Patent.

DIAEHB-AGM 130R STEAM TURBINES.

Patented Au 22, 1922.

Application filed-January .5, 1921, Serialli'o. 43 1,4416. Renewed July 3, 1922. Serial No. 572,679.

To aZZ whom it may concern:

Be it known that T, CARL It. WALLER, a citizen of the United States, residing at Trenton, county of Mercer, and State of New Jersey, have invented a new and useful Improvement in Diaphragms for Steam Turbines, of which the following is a full, clear, and exact description, reference be ing had to the accompanying drawmgs, which form a part'of this specification.

This invention relates to an improvement in tubines, and more particularly to the diaphragms and the method or means of constructing and mounting the diaphragms The object of my invention is to provide a rigid diaphragm built upof a plurality of elements in which the nozzle vanes are properly spaced, and positioned with relation to each other and held in their correct angular positions.

Another object of my invention 18 to provide an improved diaphragm which can readily be placed in position in the turb ne casing and in which the danger of forming a rust joint between the diaphragm and the casing is eliminated, and atthe same time maintain tightjoints, so that the parts can readily be taken-apart for inspection or repairs. The precise nature of my invention will be best understood by reference to the drawings, which will now be described, it being premised, however, that changes may be made within the scope of the appended claims.

Fig. 1 of the drawings is a vertical longitudinal section of a portion of aturbine with one form of my invention illustrated therein.

Fig. 2 is a similar view on a larger scale, showing a portion of one of the turbine wheels, a diaphragm and the casing.

In these drawings, the reference character 3 designates the turbine casing formed of separable members secured to each other in the usual manner, and a is the turbine shaft, which is rotatably mounted in bearings 5,

supported on the casing. Mounted on the shaft 8 on interposed tapered sleeves 6 are the wheels 7 which are arranged to be driven by the actuating fluid passing through the turbine. Seated in annular grooves 8 in the casing 3 are diaphragms each having a body portion 9, radial nozzle vanes or buckets 10, an outer ring 11 and seating rings 12, there being a diaphragm between adjacent wheels as well as one in front of the first wheel, the vanes of which are arranged to direct the actuating fluid into the path of the vanes on'the wheels.

The diaphragms are each provided with a central opening surrounding the hub of its wheel 7, and mounted in each opening is a ring 13 having annular grooves in which are seated annular brass strips 14 having beveled portions which engage the hub of the wheel to prevent the leak of fluid from one compartment to another. Each ring 13 is secured in position in an annular seat in its diaphragm by means of three screws 15 vwhichengage an annular flange on the ring .thereto.

The outer ring 11 which has been first machined to size is heated to expand it and is placed in position on the vanes in its heated condition and allowed to shrink into place to secure the vanes in position between the body 9 and the ring 11. The joint forming rings 12 of non-corroding metal, such as brass, are then placed in position on the ring 11, and are rolled into the undercut seats, after which they are machined to size.

The various parts are then assembled on the shaft, and the shaft together with the assembled elements is positioned in one portion of the casing with the diaphragms in their respective grooves. The other portion of the casing is then placed in position on the diaphragms which have been properly spaced and aligned by their engagement with the grooves 8 in the one portion of the easing, and the two portions of the casing are then bolted to each other.

As there is a good joint formed between the seating rings 12 and the faces of the grooves 8 and between the hubs of the Wheels and the brass strips 14, the actuating fluid is constrained to pass between the vanes 10 in its flow through the turbine.

As the seating rings are formed of a noncorrodible metal, there is no danger of forming a rust joint between the diaphragms, which are formed of ferrous material and the cast iron casing. This is an important feature as it permits the turbine to be readily taken apart for repairs or inspection Without breaking rust joints.

By undercutting the seats for the seating rings, rolling the rings into their seats and then machining the rings,I am enabled to form a substantially integral outer ring structure formed of three members of dissimilar metal, Without additional securing means, which can be machined to size after assembling, and which can then be handled Without danger of coming apart when handled.

The advantages of my invention result from the provision of anon-corrodible lining betWeenthe casing and the diaphragm of a turbine, Which will prevent theformation of a rust fioint between the diaphragm and the casing, so that the casing can'readily be removed for repairs-or inspection after the turbine has been in'service, Without the necessity of breaking rust joints.

A further advantage results from the pro vision of a "built up diaphragm having a body of cast iron and an outer ring of iron or "steel shrunk in position about vanes or buckets spaced about the body to secure the vanes in position, togetherWith'brass,bronze or rings of other 'non-corrodible metal positioned in undercut grooves in the outer ring.

- A further advantage results "from the provision of a method of making a built up diaphragm for turbines formed of iron or steel, having seatlng rings formed of brass,

bronze or other non-'corrodible metal, Wherefby I am enabled to secure the various parts to each other Without securing devices.

Havlng 110W fully descrlbed my'lnvention,

What i claim and desire to protect by Letters Patent is 1. A turbine having a casing Witha groove for a diaphragm, a diaphragm having an annular seat on each side thereof, and a noncorrodible metallic liner mounted on each seat, each liner engaging one of said seats.

2. A turbine having a cast iron casing Wit-h a diaphragm seating groove'therein, a "ferrous metal diaphragm seated therein and having an annular seat oneach side thereof, and a .non-corrodible metallic ring mounted on each side of the diaphragm, each ring having an annular flange engaging the inner Wall of: the casing at the edges of the seating groove. I

3. A diaphragm for a turbine having an iron body portion, vanes spaced about the body portion, a steel ring shrunk in position about the vanes to hold the vanes in position between said ring and the body portion, said ring having annular seats thereon, and a brass ring seated on'each of said seats.

4. A diaphragm for a turbine having an iron body portion, vanes spaced about the bodyportion, a steel ring shrunk in position about the vanes to hold the vanes in position betvveensaid ring and the-body portion, said ring having undercut annular seats thereon,

and brass rings in said seats.

5; A. dlaphragm for a turblne having an iron body portlon, vanes spaced about the body portion, pins engaging openings in the vanes and the periphery of thebody to position said. vanes, a steel ring shrunk in position about the vanes to hold the vanes'in position between said ringand the bodyportion, said ring having annularseats thereon, and a brass ring seated in each of said'seats.

In testimonyof which invention, I have hereunto set my hand, at Trenton, N. J., on this 30th day of Dec, 1920.

"CARL R. WALLE-R. 

